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From: allanh@netcom.UUCP (Allan N. Hessenflow)
Newsgroups: comp.sys.mac.programmer
Subject: MPW C 3.1 vs 3.0
Keywords: undocumented change?
Message-ID: <11841@netcom.UUCP>
Date: 8 May 90 18:02:43 GMT
Organization: NetCom- The Bay Area's Public Access Unix System {408 249-0290 guest}
Lines: 18

I recently recompiled an old program which worked fine with MPW C 3.0; it broke
with MPW C 3.1.  I discovered that the problem was a bug in my code which
got by because of a bug in C 3.0 (at least I think it's a bug; I'm not certain
how the language behavior is defined in this case).  This change doesn't seem
to be documented in the C 3.1 release notes.  I had something like:

long count;
...
if (count < 0xf0000000L) {
...

count should have been an 'unsigned long'.  With C 3.0, if count was, say, 1,
the test was true (it did an unsigned comparison for some reason), while with
C 3.1 it's false.


-- 
Allan N. Hessenflow   {apple|claris}!netcom!allanh    allanh@netcom.uucp